Abstract: In order to explore the quality evaluation methods of coffee beans in China when they are used for both fresh ground coffee and instant coffee, and to screen the evaluation indicators, firstly, the main quality indicators are selected from the basic quality indicators through Delphi evaluation method and sequence relationship analysis method, and the quality index system is constructed. Then determine the difference of the main quality indicators of 53 coffee bean samples from different production areas in Yunnan Province and Hainan Province, screen the characteristic quality indicators of different uses of coffee beans based on correlation analysis, principal component analysis and cluster analysis, and conduct stepwise multiple linear regression analysis based on the comprehensive score of the main components of the samples. Finally, grain size, taste, flavor and carbohydrate were selected as the characteristic quality indicators of instant coffee beans; Grain size, taste, aroma and caffeine content are the characteristic quality indicators of coffee beans for freshly ground coffee. It is determined that the main varieties suitable for instant coffee are catimor and Typica, and the main production area is Yunnan Province; The main variety of coffee beans suitable for freshly ground coffee is catimor, and the main production area is Yunnan Province.

Key words: coffee beans, quality evaluation, principal component analysis, characteristic index, index screening